ATMOSPHERE

The largest deposits of methane gas, however, may be the oceans and vast tundra wastelands. In cold water, for example, methane can form crystal structures somewhat similar to water ice known as clathrates. Clathrates are known to occur on the edges of the oceans' continental shelves. They also occur in the permafrost of tundra regions. When warmer temperatures occur, the clatharates destabilize, releasing the stored methane. The increase in the greenhouse effect that would result from the release of methane from clathrates on the continental shelves and in permafrost worldwide could equal that from the carbon dioxide produced from the burning of all the world's coal reserves.

The buildup of greenhouse gases is not the only atmospheric concern. The concentration of chlorofluorocarbons (CFC's) in the atmosphere has increased since they were first synthesized more than 70 years ago.